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Bacterial infections still present a significant concern in orthopedic and dental implant failure. Previous investigations have focused on modifying the surface texture, roughness, or coating implants with antibiotics to provide enhanced anti‐bacterial properties. However, they have demonstrated limited success. In this study, we attempted to engineer the titanium (Ti) alloy surface biomimetically at the nano level using alkaline hydrothermal treatment (AHT) inspired by cicada's wing structure. Two modified surfaces of Ti plates were developed using 4 and 8‐hr AHT at 230°C. We found that the control plates showed a relatively smooth surface, with little artifacts on the surface. In contrast, 4‐hr AHT and 8‐hr AHT plates showed nano‐spikes of heights around 250–350 and 100–1,250 nm, respectively, that were distributed randomly all over the surface. We found a statistically significant (p < 0.05) number of non‐viable cells for bothS. aureusandP. aeruginosabacterial strains when incubated for 1 hr in a dynamic environment when compared with the control group. The 8‐hr AHT groups killed 38.97% moreS. aureusin static culture and 11.27% in a dynamic environment than the 4‐hr AHT. Overall, the findings indicate that the nanostructures generated on titanium by the AHT showed significant bactericidal properties. We, therefore, recommend conducting alkaline hydrothermal treatment on the surfaces for future orthopedic and dental metallic implants.

 

Abstract Recent advances in materials and manufacturing processes have allowed the fabrication of intricate implant surfaces to facilitate bony attachment. However, refinement and evaluation of these new design strategies are hindered by the cost and complications of animal studies, particularly during early iterations in the development process. To address this problem, we have previously constructed and validated an ex-vivo bone bioreactor culture system that can maintain the viability of bone samples for an extended period ex-vivo. In this study, we investigated the mineralization of a titanium wire mesh scaffold under both static and dynamic culturing using our ex vivo bioreactor system. Thirty-six cancellous bone cores were harvested from bovine metatarsals at the time of slaughter and divided into five groups under the following conditions: Group 1) Isolated bone cores placed in static culture, Group 2) Unloaded bone cores placed in static culture in contact with a fiber-mesh metallic scaffold, Group 3) Bone cores placed in contact with a fiber-mesh metallic scaffold under the constant pressure of 150 kPa, Group 4) Bone core placed in contact with a fiber-mesh metallic scaffold and exposed to cyclic loading with continuous perfusion flow of media within the ex-vivo culture system and Group 5) Bone core evaluated on Day 0 to serve as a positive control for comparison with all other groups at weeks 4 and 7. Bone samples within Groups 1–4 were incubated for 4 and 7 weeks and then evaluated using histological examination (H&E) and the Live-Dead assay (Life Technologies). Matrix deposits on the metallic scaffolds were examined with scanning electron microscopy (SEM), while the chemical composition of the matrix was measured using energy-dispersive x-ray spectroscopy (EDX). We found that the viability of bone cores was maintained after seven weeks of loading in our ex vivo system. In addition, SEM images revealed crystallite-like structures on the dynamically loaded metal coupons (Group 4), corresponding to the initial stages of mineralization. EDX results further confirmed the presence of carbon at the interface and calcium phosphates in the matrix. We conclude that a bone bioreactor can be used as an alternate tool for in-vivo bone ingrowth studies of new implant surfaces or coatings. 

Polyether ether ketone (PEEK) is an organic polymer that has excellent mechanical, chemical properties and can be additively manufactured (3D-printed) with ease. The use of 3D-printed PEEK has been growing in many fields. This article systematically reviews the current status of 3D-printed PEEK that has been used in various areas, including medical, chemical, aerospace, and electronics. A search of the use of 3D-printed PEEK articles published until September 2021 in various fields was performed using various databases. After reviewing the articles, and those which matched the inclusion criteria set for this systematic review, we found that the printing of PEEK is mainly performed by fused filament fabrication (FFF) or fused deposition modeling (FDM) printers. Based on the results of this systematic review, it was concluded that PEEK is a versatile material, and 3D-printed PEEK is finding applications in numerous industries. However, most of the applications are still in the research phase. Still, given how the research on PEEK is progressing and its additive manufacturing, it will soon be commercialized for many applications in numerous industries. 

This study aimed to provide a review of the current status of the biomimetic adhesives that have the potential for clinical application. Biomimetic materials emulate compounds and properties with a biological origin. They have grown to be more relevant in medical fields due to biocompatibility, low toxicity, and a less damaging impact on the environment. Bonding living tissues has proved to be difficult due to the adverse immune reactions to foreign materials and the wet environment of the damaged area. There is a need for biomimetic adhesives due to the shortcomings of synthetic adhesives and metal tools required for wound closure. Despite differences in developmental approaches and organismal properties, the biomimetic adhesives developed have the potential to be used in wet environments with enough strength to help bond the tissues together without any supporting materials. 

Most chemical engineering core classes are best taught when students are exposed to a face-to-face learning/teaching environment. With the arrival of coronavirus disease 2019 (COVID-19), the whole education system and the setting were disrupted at Hampton University (HU). Traditional in-person face-to-face classes were forced to move to remote instructions to maintain a healthy and safe campus environment and minimize the spread of COVID-19 on campus and in the community. As an instructor teaching core courses and unit operations laboratory in the Department of Chemical Engineering, it was challenging to move completely virtual and deliver instructions remotely without affecting students' learning outcomes. However, with the appropriate modern technologies and adapting to the students' change and needs, online teaching can be done efficiently and can still have efficient learning outcomes. Various activities were introduced to make the online/virtual class environment engaging in developing technical and professional skills and inducing learning for students. Using the latest educational tools and online resources, formative assessments were conducted throughout the course in an effort to improve student learning and instructor teaching. In addition to that, innovative ways of technology were also used to evaluate student learning and understanding of the material for grading and reporting purposes. Many of the modern educational tools, including Blackboard Collaborate Ultra, Ka-hoot, linoit, surveys, polls, and chemical engineering processes’ simulations and videos were in-troduced to make the synchronous sessions interactive. Likert-like surveys conducted were anal-yses to gauge the effectiveness of incorporation of technology during remote learning. This paper describes the innovative use of technologies to adapt to the COVID-19 pandemic in the Chemical Engineering Classes. It will also explain the strategies to assess the mode of delivery efficacy and how to change the course of teaching to adapt to the students' changing needs.